Process condensation recovery device for high-concentration alkali device

Abstract

The utility model relates to the technical field of chemical engineering, and provides a process condensation recovery device of a high-concentration alkali device, which solves the problem that the quality of produced high-concentration liquid alkali is unstable due to design defects of the conventional device, and comprises a multi-effect evaporator, a flash tank, a condenser and a process condensate tank which are connected in sequence, the process condensate tank is connected with a first liquid conveying pipe; the device further comprises an electrolytic bath and an alkali bath, the electrolytic bath is provided with an alkali outlet, the alkali outlet is connected with a second liquid conveying pipe, the other end of the first liquid conveying pipe is connected with one side of the second liquid conveying pipe, the other end of the second liquid conveying pipe is connected with the alkali bath, and the alkali bath is connected with the multi-effect evaporator; the first liquid conveying pipe is provided with a regulating valve and a flow meter, the second liquid conveying pipe is provided with a concentration detector, and the regulating valve, the flow meter and the concentration detector are matched to stabilize the concentration of liquid alkali flowing into the alkali tank, so that the quality of the high-concentration liquid alkali is stabilized.

Description

Technical Field

[0001] The utility model relates to the technical field of chemical industry, in particular to a high concentration alkali device process condensation recovery device. Background Art

[0002] Chinese patent publication number CN209468145U discloses a chlor-alkali multi-effect evaporation condensate water recovery device, including a first-effect evaporator, a second-effect evaporator, a third-effect evaporator, a surface condenser, a low-temperature condensate water tank, a cathode liquid high-level tank and an electrolytic cell; after the first-effect evaporator is connected to the boiler steam pipeline, it is sequentially connected to the second-effect evaporator, the third-effect evaporator, the surface condenser, and the low-temperature condensate water tank; the second-effect evaporator and the third-effect evaporator are both connected to the low-temperature condensate water tank, the low-temperature condensate water tank is connected to the first feed port of the cathode liquid high-level tank, the electrolytic cell is connected to the discharge port of the cathode liquid high-level tank, and at the same time, the second feed port of the cathode liquid high-level tank is connected to the alkali liquid circulation tank.

[0003] The utility model uses the secondary steam condensed water to concentrate the dry concentration alkali product, and then uses it as the ion membrane cathode feed water, and mixes it with the waste liquid from the electrolytic cell in the alkali liquid circulation tank and then passes it into the electrolytic cell. The electrolytic cell is one of the devices for producing liquid alkali. The electrolyte in the electrolytic cell is heated to a certain temperature, and after power is turned on, an electrolytic reaction occurs under the action of the electrode, and the water in the electrolyte is decomposed into hydrogen and oxygen. At the same time, sodium hydroxide is also produced, and the sodium hydroxide is gradually precipitated at the bottom of the electrolytic cell to form liquid alkali. Generally speaking, the concentration of the liquid alkali is between 30% and 50%, and then the liquid alkali is purified by an evaporator. Since the concentration of the liquid alkali from the electrolytic cell is not stable, directly passing it into a first-effect evaporator, a second-effect evaporator and a third-effect evaporator will result in unstable quality of the generated high-concentration liquid alkali. In addition, the condensed water generated by the first-effect evaporator, the second-effect evaporator and the third-effect evaporator has a high temperature and contains a certain amount of alkali. If it is passed into a salting pool, it will affect the salting efficiency and production process control. Utility Model Content

[0004] Therefore, in view of the above problems, the utility model provides a high concentration alkali device process condensation recovery device to solve the problem of unstable quality of high concentration liquid alkali produced by the existing device due to design defects.

[0005] In order to achieve the above object, the utility model is realized by the following technical solutions:

[0006] A high concentration alkali device process condensation recovery device, comprising:

[0007] A multiple-effect evaporator, which is used to evaporate the water vapor in the liquid alkali into condensate;

[0008] A flash tank, into which the condensate generated by the multiple-effect evaporator is passed;

[0009] a condenser, the condenser being connected to the flash tank;

[0010] A process condensate tank, the process condensate tank is connected to the condenser, and the process condensate tank is connected to a first liquid infusion pipe;

[0011] An electrolytic cell, wherein the electrolytic cell is provided with an alkali outlet, the alkali outlet is connected to a second infusion tube, and the other end of the first infusion tube is connected to one side of the second infusion tube;

[0012] an alkali tank, the other end of the second liquid infusion pipe is connected to the alkali tank, and the alkali tank is connected to the multiple-effect evaporator;

[0013] A regulating valve, the regulating valve being arranged on the first infusion tube;

[0014] A flow meter, the flow meter is arranged on the first infusion tube;

[0015] A concentration detector is arranged at the connection between the second infusion tube and the alkali tank.

[0016] Furthermore, the multi-effect evaporator is a triple-effect evaporator.

[0017] Furthermore, the mass concentration of the liquid alkali in the alkali tank is 32%.

[0018] Furthermore, the mass concentration of liquid caustic soda after water vapor is evaporated from the multiple-effect evaporator is 50%.

[0019] Furthermore, the first infusion tube is provided with an infusion pump.

[0020] Furthermore, the pressure in the first infusion tube is controlled at 0.3-0.4 MPa, and the flow rate is controlled at 30 m / s. 3 / h.

[0021] Furthermore, the multi-effect evaporator, flash tank, condenser, process condensate tank, first infusion pipe, electrolytic cell, second infusion pipe, alkali tank, regulating valve and flow meter adopt anti-corrosion equipment.

[0022] Furthermore, the pH value of the condensate generated by the multiple-effect evaporator is 11.5-12.

[0023] Compared with the prior art, the beneficial effects of the utility model are:

[0024] 1. The utility model uses the condensate generated by the multiple-effect evaporator to stabilize the concentration of the liquid alkali generated in the electrolytic cell, rather than passing it to the salt-making device, so as to avoid the problem of production stability being affected by the excessively high temperature of the condensate and eliminate the problem of excessive NaOH content in the saturated brine caused by the high pH of the condensate.

[0025] 2. The utility model stabilizes the night alkali concentration flowing into the alkali tank through the cooperation of the regulating valve, the flow meter and the concentration detector, thereby stabilizing the quality of the high-concentration liquid alkali. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the structure of an embodiment of the utility model.

[0027] Description of Figure Numbers

[0028] Multiple-effect evaporator 1; flash tank 2; condenser 3; process condensate tank 4; first liquid infusion pipe 5;

[0029] Electrolytic cell 6; alkali outlet 7; second liquid infusion pipe 8; alkali tank 9; regulating valve 10; flow meter 11;

[0030] Concentration detector 12; infusion pump 13. DETAILED DESCRIPTION

[0031] The following will describe the implementation methods of the present invention in detail in conjunction with specific embodiments, so that the implementation process of how the present invention applies technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.

[0032] Example

[0033] like Figure 1 As shown, a high concentration alkali device process condensation recovery device comprises:

[0034] A multiple-effect evaporator 1, wherein the multiple-effect evaporator 1 is used to evaporate the water vapor in the liquid alkali into condensate;

[0035] Flash tank 2, the condensate generated by the multi-effect evaporator 1 carries part of the steam into the flash tank 2, the flash tank 2 converts all of the steam into steam and then passes it into the condenser 3, and part of the alkali dissolved in the condensate is recovered;

[0036] A condenser 3, wherein the condenser 3 is connected to the flash tank 2, and the condenser 3 reliquefies the steam from the flash tank 2 into a condensate;

[0037] a process condensate tank 4, wherein the process condensate tank 4 is connected to the condenser 3, and the condensate from the condenser 3 is collected in the process condensate tank 4, and the process condensate tank 4 is connected to a first liquid infusion pipe 5;

[0038] An electrolytic cell 6, wherein the electrolytic cell 6 is provided with an alkali outlet 7, the alkali outlet 7 is connected to a second infusion tube 8, and the other end of the first infusion tube 5 is connected to one side of the second infusion tube 8;

[0039] an alkali tank 9, the other end of the second liquid infusion pipe 8 is connected to the alkali tank 9, and the alkali tank 9 is connected to the multiple-effect evaporator 1;

[0040] A regulating valve 10, wherein the regulating valve 10 is arranged on the first infusion tube 5;

[0041] A flow meter 11, wherein the flow meter 11 is arranged on the first infusion tube 5;

[0042] A concentration detector 12, which is arranged at the connection between the second infusion tube 8 and the alkali tank 9;

[0043] The first infusion tube 5 is provided with an infusion pump 13. The pressure in the first infusion tube 5 is controlled at 0.35 MPa and the flow rate is controlled at 30 m / s. 3 / h;

[0044] The multi-effect evaporator 1, flash tank 2, condenser 3, process condensate tank 4, first infusion pipe 5, electrolytic tank 6, second infusion pipe 8, alkali tank 9, regulating valve 10, flow meter 11, concentration detector 12 and infusion pump 13 adopt anti-corrosion equipment;

[0045] The condensate generated by the multiple-effect evaporator 1 is used to stabilize the concentration of the liquid caustic soda generated by the electrolytic cell 6, rather than being passed to the salt-making device, so as to avoid the problem of production stability being affected by the excessively high temperature of the condensate, and eliminate the problem of excessive NaOH content in the saturated brine caused by the high pH value of the condensate; the night caustic soda concentration flowing into the caustic soda tank 9 is stabilized by the cooperation of the regulating valve 10, the flow meter 11 and the concentration detector 12, thereby stabilizing the quality of the high-concentration liquid caustic soda;

[0046] The multiple-effect evaporator 1 adopts a triple-effect evaporator, which is a conventional device in the art and will not be described in detail here; the pH value of the condensate generated by the multiple-effect evaporator 1 is 11.5, and the concentration detector 12 adopts a sodium hydroxide concentration detector, which can be purchased from the market and will not be described in detail here;

[0047] The mass concentration of the liquid alkali in the alkali tank 9 is 32%, and the mass concentration of the liquid alkali after the water vapor is evaporated from the multiple-effect evaporator 1 is 50%. The determined liquid alkali concentration is convenient for determining the parameter setting of the multiple-effect evaporator 1, which is conducive to stable production.

[0048] Although the present invention has been specifically demonstrated and described in conjunction with the preferred embodiments, those skilled in the art should understand that various changes may be made to the present invention in form and detail without departing from the spirit and scope of the present invention as defined in the appended claims, all of which are within the scope of protection of the present invention.

Claims

1. A condensation recovery device for a high concentration alkali device process, characterized in that: include: A multiple-effect evaporator, which is used to evaporate the water vapor in the liquid alkali into condensate; A flash tank, into which the condensate generated by the multiple-effect evaporator is passed; a condenser, the condenser being connected to the flash tank; A process condensate tank, the process condensate tank is connected to the condenser, and the process condensate tank is connected to a first liquid infusion pipe; An electrolytic cell, wherein the electrolytic cell is provided with an alkali outlet, the alkali outlet is connected to a second infusion tube, and the other end of the first infusion tube is connected to one side of the second infusion tube; an alkali tank, the other end of the second liquid infusion pipe is connected to the alkali tank, and the alkali tank is connected to the multiple-effect evaporator; A regulating valve, the regulating valve being arranged on the first infusion tube; A flow meter, the flow meter is arranged on the first infusion tube; A concentration detector is arranged at the connection between the second infusion tube and the alkali tank.

2. A condensation recovery device for a high concentration alkali device process according to claim 1, characterized in that: The multi-effect evaporator adopts a triple-effect evaporator.

3. The high concentration alkali device process condensation recovery device according to claim 1, characterized in that: The first infusion tube is provided with an infusion pump.

4. The high concentration alkali device process condensation recovery device according to claim 1, characterized in that: The pressure in the first infusion tube is controlled at 0.3-0.4 MPa, and the flow rate is controlled at 30 m 3 / h.

5. The high concentration alkali device process condensation recovery device according to claim 1, characterized in that: The multi-effect evaporator, flash tank, condenser, process condensate tank, first infusion pipe, electrolytic tank, second infusion pipe, alkali tank, regulating valve and flow meter are anti-corrosion equipment.

6. The high concentration alkali device process condensation recovery device according to claim 1, characterized in that: The pH value of the condensate generated by the multiple-effect evaporator is 11.5-12.

Images